1. Field of the Invention
The present invention relates to a printing apparatus connected to a host which prints on roll paper and which is equipped with a roll paper cutting unit.
2. Description of the Related Art
Among conventional printing apparatuses which are connected to a host, a roll paper printing apparatus which prints on roll paper typically cut the roll paper with a roll paper cutting unit after the printing and obtains printed matter.
FIG. 5 is a diagram illustrating a conventional roll paper printing apparatus 200.
In the conventional roll paper printing apparatus 200, first, roll paper conveyance units 31 convey a roll paper RP1 to a print head H1 in the direction illustrated by large arrows. Ink is supplied to the print head H1 from an ink tank 61. While being moved by a print head conveyance unit 62, the print head H1 prints by discharging ink on the roll paper RP1.
After printing is completed, a cutter C1 which is a roll paper cutting unit is driven by a cutter conveyance unit 63 to cut the printed roll paper RP1, and desired printed matter is output.
Further, a roll paper cutting instruction determination unit (not illustrated) is provided in the conventional roll paper printing apparatus 200. Depending on contents of the roll paper cutting instruction included in print job data, a printing operation may be finished without cutting the printed roll paper with the cutter C1. The printing operation which is finished without performing cutting with the cutter C1 will hereinafter be referred to as “no-cut printing”.
FIG. 6 is a diagram illustrating one sheet of consecutive print results 71 in a conventional example.
According to the above-described method, as illustrated in FIG. 6, one sheet of consecutive print results 71 is obtained by consecutively transmitting a plurality of pieces of no-cut print job data from the host. Hereinafter, “one sheet of consecutive print results” will be referred to as “banner printing”.
In the example illustrated in FIG. 6, the plurality of pieces of no-cut print job data is configured from individual no-cut print jobs A, B, and C demarcated by lines 72. These pieces of job data are consecutively transmitted to the roll paper printing apparatus 200 to form the print results.
When a banner printing method is used and the no-cut print job data are consecutively received, an interrupt print job from another host may be transmitted during the banner printing.
In such a case, interrupt printing is performed with other print job data in the midst of the consecutive printed matter, so that a user cannot obtain intended banner print results. To solve this problem, Japanese Patent Application Laid-Open No. 2006-88364 discusses a roll paper printing apparatus which does not perform interrupt printing when the interrupt printing is requested if a no-cut print job is present in the roll paper printing apparatus.
In the roll paper printing apparatus 200 discussed in Japanese Patent Application Laid-Open No. 2006-88364, when an interrupt print job is received in a state where the no-cut print job is present, the interrupt print job is registered at an end of a queue of already-received print jobs.
FIGS. 7A to 7D are diagrams illustrating job receiving orders transmitted from a plurality of hosts X and Y and interrupt job print results of the conventional roll paper printing apparatus 200.
As illustrated in FIG. 7A, when a plurality of no-cut print jobs A, B, and C are consecutively transmitted from the host X and one print result is to be obtained, a desired print result can be obtained, as shown in a print result column of FIG. 7C.
However, as illustrated in FIG. 7B, when the plurality of no-cut print job data is consecutively transmitted, depending on host performance and the like, a transmission interval may open up between the print jobs. In such a case, as illustrated in FIG. 7B, if an interrupt print job Z is received from the host Y midway through the transmission interval of the no-cut print jobs A, B, and C transmitted from the host X, the interrupt print job Z is printed between the consecutive print jobs A and B. As a result, as shown in a print result column of FIG. 7D, there is the problem that a desired banner print result cannot be obtained.